Tiger & Bunny: Various

I would like to add that the Pizza Hut references are edited out of the English localized version of Code Geass, in the Japanese version you can see the Pizza Hut logo clearly when the Pizza is being delivers to C.C, however in the english version either the logo has been totally removed or just the text with hat part made a bot more bluring
– Memor-XOct 26 '14 at 21:38

Well, there's Tiger & Bunny which plastered product placement to the extreme of its real-life sponsors:

Each of the city's most famous superheroes work for a sponsor company and their uniforms also contain advertising for real-life companies.

The show features "sponsored" super heroes who fight crime, with their sponsors plastered all over them like NASCAR, and in some cases, even doing in-show commercials for the actual product (e.g. Pepsi). Some of these in-show sponsors were actually sponsors of the show. The old Tiger & Bunny website (it's since been changed) listed all of their sponsors which had product placement: via archive.org.

I don't know if these companies actually went to the producers to pay for advertising spots within the show. It's probably more likely that it was a two-way street, working much like how anime get made in general, where the producers/studio will look for sponsors with an idea, and a contract and agreement is made. So these companies went into it knowing how their product would be placed in the show.

When the show was adapted into a manga, all of the product placement was removed (for obvious reasons).

I'm not sure it was actually a paid product placement. Is there any source confirming the show makers got paid to do that and it wasn't a joke involving a real brand name? Coz you know, Nichijou is full of humor.
– HakaseOct 25 '14 at 14:19

The Katsuhiro Otomo-designed Freedom OAV series is a particularly fun viewing experience for product placement, since it came into being as part of a Nissin Cup Noodles promotional campaign. In it, remnants of humanity live in a lunar colony where -- incidentally and inexplicably -- Nissin Cup Noodles are a primary food source.